Greg Reddick is a noted speaker, author, and software engineer. This blog covers all aspects of programming, particularly for Windows, and other related topics.

2015-08-17

Uninstall Cisco VPN Software Before Upgrading to Windows 10

I tried to upgrade a Microsoft Surface Pro 3 from Windows 8.1 to Windows 10. Windows 10 upgraded, but it would not recognize the network drivers. This is a real pain because you can't install anything that would fix it from the network, and instead have to use another machine and copy files over using a USB stick.

After doing some research, I discovered that multiple people have reported this problem. It occurs because the Surface had the Cisco VPN software installed. The normal way people have fixed this is to revert back to the previous operating system, then remove the Cisco software, then reinstall Windows 10 (a crazy amount of work and time). However, when I tried to revert, something was messed up and it told me I didn't have the files to revert.

I finally just wound up searching the machine for every file related to DNE (Deterministic Network Enhancer) and Cisco and killing them. Then I searched the registry for all entries related to DNE and Cisco deleted those. (As always, be real careful when messing with the registry or you can permanently damage Windows!) This took hours: the revert and reinstall would have been faster. After a reboot, the network came back up.

Cisco shouldn't have this problem, but Microsoft's upgrade should have worked around this. It's both of their fault.TL;DR: Uninstall the Cisco VPN software before trying to upgrade to Windows 10. Then reinstall it after you are done with the upgrade. If you've already upgraded, revert (if you can), uninstall the VPN software, and upgrade again.